Which term describes a substance made up of atoms of two or more different elements joined by chemical bonds?

Which term describes a substance made up of atoms of two or more different elements joined by chemical bonds?

• A. Compound
• B. Molecule
• C. Element
• D. Alloy

Answer: (A)

A substance made of atoms from two or more different elements joined by chemical bonds is a compound. The key idea is that the elements are chemically bonded in a specific, fixed ratio, forming a new substance with properties distinct from the individual elements. Water is a classic example: hydrogen and oxygen combine in a 2:1 ratio to make H2O, which behaves very differently from either gas. A molecule is a general term for a bonded group of atoms and can be composed of the same element (like O2) or different elements (like H2O). So while many molecules are compounds, the defining feature described here is the chemical bonding of different elements in a definite composition, which is what defines a compound. An element is just one type of atom, so it cannot be two different elements. An alloy is typically a metal mixture, not a pure substance with a fixed chemical formula formed by chemically bonded elements, so it doesn’t fit this definition as neatly.

A substance made of atoms from two or more different elements joined by chemical bonds is a compound. The key idea is that the elements are chemically bonded in a specific, fixed ratio, forming a new substance with properties distinct from the individual elements. Water is a classic example: hydrogen and oxygen combine in a 2:1 ratio to make H2O, which behaves very differently from either gas. A molecule is a general term for a bonded group of atoms and can be composed of the same element (like O2) or different elements (like H2O). So while many molecules are compounds, the defining feature described here is the chemical bonding of different elements in a definite composition, which is what defines a compound. An element is just one type of atom, so it cannot be two different elements. An alloy is typically a metal mixture, not a pure substance with a fixed chemical formula formed by chemically bonded elements, so it doesn’t fit this definition as neatly.